J. W. Chen

Upper critical magnetic field of the superconducting heavy fermion system (U1−x Thx)Be13

Measurements of the ac electrical resistance as a function of temperature and applied magnetic field R(T,H) were made for various compositions x≲0.03 in the mixed binary system (U1−xThx)Be13. All samples within this range of x exhibit heavy Fermion superconductivity with a superconducting transition temperature Tc that is rapidly suppressed by the substitution of Th for U. The shape of the upper critical field curve Hc2(T) determined from the R(T,H) data is similar for all compositions with a very large initial slope (−dHc2/dT)Tc.

Magnetic and superconducting properties of single crystals of rare earth rhodium boride compounds RRh4B4

Abstract Small single crystals of RRh 4 B 4 compounds where R = Sm, Gd, Tb, Dy, Ho, Er, Tm, Lu, and Y have been prepared by precipitation from a molten copper flux. Measurements of the low frequency ac electrical resistance R are reported with particular emphasis on the behavior of R for temperatures T less than the magnetic ordering temperature. The upper critical magnetic field of ErRh 4 B 4 determined from R ( T ) measurements in applied magnetic fields is presented for parallel and perpendicular orientations of the tetragonal c -axis of the sample with respect to the applied magnetic field. Comparisons are made with previous work on polycrystalline samples of all the compounds as well as single crystals of ErRh 4 B 4 .

Anisotropic magnetic and superconducting properties of single crystals of RERh4B4 compounds

We report the synthesis of small single crystals of several RERh4B4 compounds where RE=Sm, Gd, Tb, Dy, Ho, Er, and Tm using a flux‐growth technique. Measurements of the ac electrical resistance R in zero and applied magnetic fields and dc magnetic susceptibility are reported. The upper critical magnetic field Hc2(T) determined from the resistance measurements for RE=Sm, Er, and Tm are also presented. Considerable anisotropy of Hc2(T) is observed for Er and Tm, while very little is found for Sm.

Anisotropic magnetic and superconducting properties of single crystals of RERh/sub 4/B/sub 4/ compounds

We report the synthesis of small single crystals of several RERh4B4 compounds where RE=Sm, Gd, Tb, Dy, Ho, Er, and Tm using a flux‐growth technique. Measurements of the ac electrical resistance R in zero and applied magnetic fields and dc magnetic susceptibility are reported. The upper critical magnetic field Hc2(T) determined from the resistance measurements for RE=Sm, Er, and Tm are also presented. Considerable anisotropy of Hc2(T) is observed for Er and Tm, while very little is found for Sm.